Single phase is 10kW, but no limit on the number of kWh. Some plans drop the daily feed-in rate after 14kWh. <edit> it turns out this is far more complicated. Different states and different suppliers as well as different regions have different limits. Ausgrid in NSW permit a maximum of 10kW feed-in for single phase. BUT elsewhere there are miriad of different limits. Many are 5 kW, but is it safe to say, no matter where you live, you need to check with your local installers.